One of the most popular ways in which an egg is served is to have the egg white, or albumin, cooked to relative firmness while keeping the yellow or egg yolk relatively soft or “runny.” Eggs cooked in such a manner are often referred to as “sunny side up,” or “over easy.” Eggs can also be “poached,” in which case the egg white or albumin will be somewhat cooked and the yolk will be relatively soft compared to the albumin yielding somewhat similar results to a “soft boiled egg.”
When an egg is cooked with the yolk intact either on a grill or in a frying pan, the egg white spreads and as it becomes relatively thin it begins to cook rather quickly. The egg yolk also flattens somewhat and its cooking is also relatively accelerated, but not as much as the egg white (so long as the yolk remains intact). The yolk begins to cook from exposure to the heat but because it is thicker relative to the egg white, it does not cook as quickly as the egg white. If the egg is removed from the cooking heat in a timely manner, the white will be firm and the yolk will be soft and/or runny. An important aspect is that if the egg yolk does not flatten as a result of its own weight, it will cook considerable slower which in turn allows a larger margin of timing as to when the cook would have to remove the cooking egg from the heat and still achieve a firm egg white and a soft yolk.
Regarding poaching of an egg, it has been recognized that one method of poaching is to simply drop the raw egg into a pot of boiling water, which is a method sometimes used by experienced cooks. Most often, poaching of eggs is carried out by using an “egg poacher.” This device consists of a larger pan and a platform within the larger pan that supports smaller pans that each holds an individual egg. The smaller pans are sized in diameter so that when the raw egg is placed in it, the yolk is essentially immersed in the albumin, which tends to yield the desired effect of shielding the yolk from receiving the heat first and thereby causing the yolk to cook slower relative to the albumin. Water is placed in the bottom of the larger pan and the individual egg pans are set in place within the larger pan. A lid is placed over the large pan and when the water begins to boil, hot steam and water vapor envelops the egg in the individual pans and cooks the egg. Again timing is critical to these poaching methods in that the egg cooks from outside inward as the heat travels inward toward the center of the egg. If the egg or eggs are removed from the heat in a timely manner, the yolk, preferably positioned in the middle of the egg mass, in the middle of the small pans will receive the heat last and will, to some extent, be less cooked than the albumin that surrounds the yolk in the small pans.
These methods of cooking an egg require a keen sense of timing and are less than an exact science. A main contributor to this is that although the desired level of cooking for the yolk versus the albumin is different, the exposure to the cooking heat is not significantly differentiated between the two components under present methods. Specifically, no effort is made to differentiate the exposure of the albumin and the yolk to the cooking heat. At best, prior cooking methods surrounded the yolk with the albumin with a goal that the surrounding albumin would cook before too much heat reaches the yolk. Accordingly, it can be very difficult to control the differentiated firmness or the “level of doneness” for each component of the egg relative to each other. For example, when the albumin is cooked to one's preferred firmness, the yolk may end up being overcooked. Conversely, by focusing on the egg yolk while cooking, the albumin can often be undercooked and end up being runny.
FIG. 1 illustrates a cooking device, which is designed for poaching eggs in boiling water. The device holds a raw egg and transmits heat from the boiling water into which it is submerged. Devices such as this do not take into consideration relative amounts of heat transferred to the albumin and egg yolk and can lead to inconsistent results where the yolk is often overcooked or the albumin is undercooked.